[mirror_ubuntu-bionic-kernel.git] / drivers / bluetooth / hci_ldisc.c

/*
 *
 *  Bluetooth HCI UART driver
 *
 *  Copyright (C) 2000-2001  Qualcomm Incorporated
 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
 *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/poll.h>

#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/signal.h>
#include <linux/ioctl.h>
#include <linux/skbuff.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#include "hci_uart.h"

#define VERSION "2.2"

static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];

int hci_uart_register_proto(struct hci_uart_proto *p)
{
	if (p->id >= HCI_UART_MAX_PROTO)
		return -EINVAL;

	if (hup[p->id])
		return -EEXIST;

	hup[p->id] = p;

	return 0;
}

int hci_uart_unregister_proto(struct hci_uart_proto *p)
{
	if (p->id >= HCI_UART_MAX_PROTO)
		return -EINVAL;

	if (!hup[p->id])
		return -EINVAL;

	hup[p->id] = NULL;

	return 0;
}

static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
{
	if (id >= HCI_UART_MAX_PROTO)
		return NULL;

	return hup[id];
}

static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
{
	struct hci_dev *hdev = hu->hdev;

	/* Update HCI stat counters */
	switch (pkt_type) {
	case HCI_COMMAND_PKT:
		hdev->stat.cmd_tx++;
		break;

	case HCI_ACLDATA_PKT:
		hdev->stat.acl_tx++;
		break;

	case HCI_SCODATA_PKT:
		hdev->stat.sco_tx++;
		break;
	}
}

static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
{
	struct sk_buff *skb = hu->tx_skb;

	if (!skb)
		skb = hu->proto->dequeue(hu);
	else
		hu->tx_skb = NULL;

	return skb;
}

int hci_uart_tx_wakeup(struct hci_uart *hu)
{
	struct tty_struct *tty = hu->tty;
	struct hci_dev *hdev = hu->hdev;
	struct sk_buff *skb;

	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
		set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
		return 0;
	}

	BT_DBG("");

restart:
	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);

	while ((skb = hci_uart_dequeue(hu))) {
		int len;

		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
		len = tty->ops->write(tty, skb->data, skb->len);
		hdev->stat.byte_tx += len;

		skb_pull(skb, len);
		if (skb->len) {
			hu->tx_skb = skb;
			break;
		}

		hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
		kfree_skb(skb);
	}

	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
		goto restart;

	clear_bit(HCI_UART_SENDING, &hu->tx_state);
	return 0;
}

static void hci_uart_init_work(struct work_struct *work)
{
	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
	int err;

	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
		return;

	err = hci_register_dev(hu->hdev);
	if (err < 0) {
		BT_ERR("Can't register HCI device");
		hci_free_dev(hu->hdev);
		hu->hdev = NULL;
		hu->proto->close(hu);
	}

	set_bit(HCI_UART_REGISTERED, &hu->flags);
}

int hci_uart_init_ready(struct hci_uart *hu)
{
	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
		return -EALREADY;

	schedule_work(&hu->init_ready);

	return 0;
}

/* ------- Interface to HCI layer ------ */
/* Initialize device */
static int hci_uart_open(struct hci_dev *hdev)
{
	BT_DBG("%s %p", hdev->name, hdev);

	/* Nothing to do for UART driver */

	set_bit(HCI_RUNNING, &hdev->flags);

	return 0;
}

/* Reset device */
static int hci_uart_flush(struct hci_dev *hdev)
{
	struct hci_uart *hu  = hci_get_drvdata(hdev);
	struct tty_struct *tty = hu->tty;

	BT_DBG("hdev %p tty %p", hdev, tty);

	if (hu->tx_skb) {
		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
	}

	/* Flush any pending characters in the driver and discipline. */
	tty_ldisc_flush(tty);
	tty_driver_flush_buffer(tty);

	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
		hu->proto->flush(hu);

	return 0;
}

/* Close device */
static int hci_uart_close(struct hci_dev *hdev)
{
	BT_DBG("hdev %p", hdev);

	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
		return 0;

	hci_uart_flush(hdev);
	hdev->flush = NULL;
	return 0;
}

/* Send frames from HCI layer */
static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
{
	struct hci_uart *hu = hci_get_drvdata(hdev);

	if (!test_bit(HCI_RUNNING, &hdev->flags))
		return -EBUSY;

	BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);

	hu->proto->enqueue(hu, skb);

	hci_uart_tx_wakeup(hu);

	return 0;
}

/* ------ LDISC part ------ */
/* hci_uart_tty_open
 *
 *     Called when line discipline changed to HCI_UART.
 *
 * Arguments:
 *     tty    pointer to tty info structure
 * Return Value:
 *     0 if success, otherwise error code
 */
static int hci_uart_tty_open(struct tty_struct *tty)
{
	struct hci_uart *hu;

	BT_DBG("tty %p", tty);

	/* Error if the tty has no write op instead of leaving an exploitable
	   hole */
	if (tty->ops->write == NULL)
		return -EOPNOTSUPP;

	if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
		BT_ERR("Can't allocate control structure");
		return -ENFILE;
	}

	tty->disc_data = hu;
	hu->tty = tty;
	tty->receive_room = 65536;

	INIT_WORK(&hu->init_ready, hci_uart_init_work);

	spin_lock_init(&hu->rx_lock);

	/* Flush any pending characters in the driver and line discipline. */

	/* FIXME: why is this needed. Note don't use ldisc_ref here as the
	   open path is before the ldisc is referencable */

	if (tty->ldisc->ops->flush_buffer)
		tty->ldisc->ops->flush_buffer(tty);
	tty_driver_flush_buffer(tty);

	return 0;
}

/* hci_uart_tty_close()
 *
 *    Called when the line discipline is changed to something
 *    else, the tty is closed, or the tty detects a hangup.
 */
static void hci_uart_tty_close(struct tty_struct *tty)
{
	struct hci_uart *hu = (void *)tty->disc_data;
	struct hci_dev *hdev;

	BT_DBG("tty %p", tty);

	/* Detach from the tty */
	tty->disc_data = NULL;

	if (!hu)
		return;

	hdev = hu->hdev;
	if (hdev)
		hci_uart_close(hdev);

	if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
		if (hdev) {
			if (test_bit(HCI_UART_REGISTERED, &hu->flags))
				hci_unregister_dev(hdev);
			hci_free_dev(hdev);
		}
		hu->proto->close(hu);
	}

	kfree(hu);
}

/* hci_uart_tty_wakeup()
 *
 *    Callback for transmit wakeup. Called when low level
 *    device driver can accept more send data.
 *
 * Arguments:        tty    pointer to associated tty instance data
 * Return Value:    None
 */
static void hci_uart_tty_wakeup(struct tty_struct *tty)
{
	struct hci_uart *hu = (void *)tty->disc_data;

	BT_DBG("");

	if (!hu)
		return;

	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);

	if (tty != hu->tty)
		return;

	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
		hci_uart_tx_wakeup(hu);
}

/* hci_uart_tty_receive()
 *
 *     Called by tty low level driver when receive data is
 *     available.
 *
 * Arguments:  tty          pointer to tty isntance data
 *             data         pointer to received data
 *             flags        pointer to flags for data
 *             count        count of received data in bytes
 *
 * Return Value:    None
 */
static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
{
	struct hci_uart *hu = (void *)tty->disc_data;

	if (!hu || tty != hu->tty)
		return;

	if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
		return;

	spin_lock(&hu->rx_lock);
	hu->proto->recv(hu, (void *) data, count);

	if (hu->hdev)
		hu->hdev->stat.byte_rx += count;

	spin_unlock(&hu->rx_lock);

	tty_unthrottle(tty);
}

static int hci_uart_register_dev(struct hci_uart *hu)
{
	struct hci_dev *hdev;

	BT_DBG("");

	/* Initialize and register HCI device */
	hdev = hci_alloc_dev();
	if (!hdev) {
		BT_ERR("Can't allocate HCI device");
		return -ENOMEM;
	}

	hu->hdev = hdev;

	hdev->bus = HCI_UART;
	hci_set_drvdata(hdev, hu);

	hdev->open  = hci_uart_open;
	hdev->close = hci_uart_close;
	hdev->flush = hci_uart_flush;
	hdev->send  = hci_uart_send_frame;
	SET_HCIDEV_DEV(hdev, hu->tty->dev);

	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);

	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
		set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);

	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
		hdev->dev_type = HCI_AMP;
	else
		hdev->dev_type = HCI_BREDR;

	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
		return 0;

	if (hci_register_dev(hdev) < 0) {
		BT_ERR("Can't register HCI device");
		hci_free_dev(hdev);
		return -ENODEV;
	}

	set_bit(HCI_UART_REGISTERED, &hu->flags);

	return 0;
}

static int hci_uart_set_proto(struct hci_uart *hu, int id)
{
	struct hci_uart_proto *p;
	int err;

	p = hci_uart_get_proto(id);
	if (!p)
		return -EPROTONOSUPPORT;

	err = p->open(hu);
	if (err)
		return err;

	hu->proto = p;

	err = hci_uart_register_dev(hu);
	if (err) {
		p->close(hu);
		return err;
	}

	return 0;
}

/* hci_uart_tty_ioctl()
 *
 *    Process IOCTL system call for the tty device.
 *
 * Arguments:
 *
 *    tty        pointer to tty instance data
 *    file       pointer to open file object for device
 *    cmd        IOCTL command code
 *    arg        argument for IOCTL call (cmd dependent)
 *
 * Return Value:    Command dependent
 */
static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
					unsigned int cmd, unsigned long arg)
{
	struct hci_uart *hu = (void *)tty->disc_data;
	int err = 0;

	BT_DBG("");

	/* Verify the status of the device */
	if (!hu)
		return -EBADF;

	switch (cmd) {
	case HCIUARTSETPROTO:
		if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
			err = hci_uart_set_proto(hu, arg);
			if (err) {
				clear_bit(HCI_UART_PROTO_SET, &hu->flags);
				return err;
			}
		} else
			return -EBUSY;
		break;

	case HCIUARTGETPROTO:
		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
			return hu->proto->id;
		return -EUNATCH;

	case HCIUARTGETDEVICE:
		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
			return hu->hdev->id;
		return -EUNATCH;

	case HCIUARTSETFLAGS:
		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
			return -EBUSY;
		hu->hdev_flags = arg;
		break;

	case HCIUARTGETFLAGS:
		return hu->hdev_flags;

	default:
		err = n_tty_ioctl_helper(tty, file, cmd, arg);
		break;
	}

	return err;
}

/*
 * We don't provide read/write/poll interface for user space.
 */
static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
					unsigned char __user *buf, size_t nr)
{
	return 0;
}

static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file,
					const unsigned char *data, size_t count)
{
	return 0;
}

static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
					struct file *filp, poll_table *wait)
{
	return 0;
}

static int __init hci_uart_init(void)
{
	static struct tty_ldisc_ops hci_uart_ldisc;
	int err;

	BT_INFO("HCI UART driver ver %s", VERSION);

	/* Register the tty discipline */

	memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
	hci_uart_ldisc.magic		= TTY_LDISC_MAGIC;
	hci_uart_ldisc.name		= "n_hci";
	hci_uart_ldisc.open		= hci_uart_tty_open;
	hci_uart_ldisc.close		= hci_uart_tty_close;
	hci_uart_ldisc.read		= hci_uart_tty_read;
	hci_uart_ldisc.write		= hci_uart_tty_write;
	hci_uart_ldisc.ioctl		= hci_uart_tty_ioctl;
	hci_uart_ldisc.poll		= hci_uart_tty_poll;
	hci_uart_ldisc.receive_buf	= hci_uart_tty_receive;
	hci_uart_ldisc.write_wakeup	= hci_uart_tty_wakeup;
	hci_uart_ldisc.owner		= THIS_MODULE;

	if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
		BT_ERR("HCI line discipline registration failed. (%d)", err);
		return err;
	}

#ifdef CONFIG_BT_HCIUART_H4
	h4_init();
#endif
#ifdef CONFIG_BT_HCIUART_BCSP
	bcsp_init();
#endif
#ifdef CONFIG_BT_HCIUART_LL
	ll_init();
#endif
#ifdef CONFIG_BT_HCIUART_ATH3K
	ath_init();
#endif
#ifdef CONFIG_BT_HCIUART_3WIRE
	h5_init();
#endif

	return 0;
}

static void __exit hci_uart_exit(void)
{
	int err;

#ifdef CONFIG_BT_HCIUART_H4
	h4_deinit();
#endif
#ifdef CONFIG_BT_HCIUART_BCSP
	bcsp_deinit();
#endif
#ifdef CONFIG_BT_HCIUART_LL
	ll_deinit();
#endif
#ifdef CONFIG_BT_HCIUART_ATH3K
	ath_deinit();
#endif
#ifdef CONFIG_BT_HCIUART_3WIRE
	h5_deinit();
#endif

	/* Release tty registration of line discipline */
	if ((err = tty_unregister_ldisc(N_HCI)))
		BT_ERR("Can't unregister HCI line discipline (%d)", err);
}

module_init(hci_uart_init);
module_exit(hci_uart_exit);

MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS_LDISC(N_HCI);
Commit	Line	Data
1da177e4	1	/*
1da177e4	2	*
0372a662 MH	3	* Bluetooth HCI UART driver
	4	*
	5	* Copyright (C) 2000-2001 Qualcomm Incorporated
	6	* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
	7	* Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
	8	*
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; either version 2 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	23	*
1da177e4	24	*/
1da177e4	25
1da177e4 LT	26	#include <linux/module.h>
	27
	28	#include <linux/kernel.h>
	29	#include <linux/init.h>
1da177e4 LT	30	#include <linux/types.h>
	31	#include <linux/fcntl.h>
	32	#include <linux/interrupt.h>
	33	#include <linux/ptrace.h>
	34	#include <linux/poll.h>
	35
	36	#include <linux/slab.h>
	37	#include <linux/tty.h>
	38	#include <linux/errno.h>
	39	#include <linux/string.h>
	40	#include <linux/signal.h>
	41	#include <linux/ioctl.h>
	42	#include <linux/skbuff.h>
	43
	44	#include <net/bluetooth/bluetooth.h>
	45	#include <net/bluetooth/hci_core.h>
	46
	47	#include "hci_uart.h"
	48
0372a662 MH	49	#define VERSION "2.2"
0372a662 MH	50
1da177e4 LT	51	static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
	52
	53	int hci_uart_register_proto(struct hci_uart_proto *p)
	54	{
	55	if (p->id >= HCI_UART_MAX_PROTO)
	56	return -EINVAL;
	57
	58	if (hup[p->id])
	59	return -EEXIST;
	60
	61	hup[p->id] = p;
0372a662	62
1da177e4 LT	63	return 0;
	64	}
	65
	66	int hci_uart_unregister_proto(struct hci_uart_proto *p)
	67	{
	68	if (p->id >= HCI_UART_MAX_PROTO)
	69	return -EINVAL;
	70
	71	if (!hup[p->id])
	72	return -EINVAL;
	73
	74	hup[p->id] = NULL;
0372a662	75
1da177e4 LT	76	return 0;
	77	}
	78
	79	static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
	80	{
	81	if (id >= HCI_UART_MAX_PROTO)
	82	return NULL;
0372a662	83
1da177e4 LT	84	return hup[id];
	85	}
	86
	87	static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
	88	{
	89	struct hci_dev *hdev = hu->hdev;
0372a662	90
1da177e4 LT	91	/* Update HCI stat counters */
	92	switch (pkt_type) {
	93	case HCI_COMMAND_PKT:
	94	hdev->stat.cmd_tx++;
	95	break;
	96
	97	case HCI_ACLDATA_PKT:
	98	hdev->stat.acl_tx++;
	99	break;
	100
	101	case HCI_SCODATA_PKT:
7f8f2729	102	hdev->stat.sco_tx++;
1da177e4 LT	103	break;
	104	}
	105	}
	106
	107	static inline struct sk_buff hci_uart_dequeue(struct hci_uart hu)
	108	{
	109	struct sk_buff *skb = hu->tx_skb;
0372a662	110
1da177e4 LT	111	if (!skb)
	112	skb = hu->proto->dequeue(hu);
	113	else
	114	hu->tx_skb = NULL;
0372a662	115
1da177e4 LT	116	return skb;
	117	}
	118
	119	int hci_uart_tx_wakeup(struct hci_uart *hu)
	120	{
	121	struct tty_struct *tty = hu->tty;
	122	struct hci_dev *hdev = hu->hdev;
	123	struct sk_buff *skb;
0372a662	124
1da177e4 LT	125	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
	126	set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	127	return 0;
	128	}
	129
	130	BT_DBG("");
	131
	132	restart:
	133	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	134
	135	while ((skb = hci_uart_dequeue(hu))) {
	136	int len;
0372a662	137
1da177e4	138	set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
f34d7a5b	139	len = tty->ops->write(tty, skb->data, skb->len);
1da177e4 LT	140	hdev->stat.byte_tx += len;
	141
	142	skb_pull(skb, len);
	143	if (skb->len) {
	144	hu->tx_skb = skb;
	145	break;
	146	}
0372a662	147
0d48d939	148	hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
1da177e4	149	kfree_skb(skb);
0372a662 MH	150	}
0372a662 MH	151
1da177e4 LT	152	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
	153	goto restart;
	154
	155	clear_bit(HCI_UART_SENDING, &hu->tx_state);
	156	return 0;
	157	}
	158
9f2aee84 JH	159	static void hci_uart_init_work(struct work_struct *work)
	160	{
	161	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
	162	int err;
	163
	164	if (!test_and_clear_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
	165	return;
	166
	167	err = hci_register_dev(hu->hdev);
	168	if (err < 0) {
	169	BT_ERR("Can't register HCI device");
	170	hci_free_dev(hu->hdev);
	171	hu->hdev = NULL;
	172	hu->proto->close(hu);
	173	}
	174
	175	set_bit(HCI_UART_REGISTERED, &hu->flags);
	176	}
	177
	178	int hci_uart_init_ready(struct hci_uart *hu)
	179	{
	180	if (!test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
	181	return -EALREADY;
	182
	183	schedule_work(&hu->init_ready);
	184
	185	return 0;
	186	}
	187
1da177e4 LT	188	/* ------- Interface to HCI layer ------ */
	189	/* Initialize device */
	190	static int hci_uart_open(struct hci_dev *hdev)
	191	{
	192	BT_DBG("%s %p", hdev->name, hdev);
	193
	194	/* Nothing to do for UART driver */
	195
	196	set_bit(HCI_RUNNING, &hdev->flags);
0372a662	197
1da177e4 LT	198	return 0;
	199	}
	200
	201	/* Reset device */
	202	static int hci_uart_flush(struct hci_dev *hdev)
	203	{
155961e8	204	struct hci_uart *hu = hci_get_drvdata(hdev);
1da177e4 LT	205	struct tty_struct *tty = hu->tty;
	206
	207	BT_DBG("hdev %p tty %p", hdev, tty);
	208
	209	if (hu->tx_skb) {
	210	kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
	211	}
	212
	213	/* Flush any pending characters in the driver and discipline. */
	214	tty_ldisc_flush(tty);
f34d7a5b	215	tty_driver_flush_buffer(tty);
1da177e4 LT	216
	217	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	218	hu->proto->flush(hu);
	219
	220	return 0;
	221	}
	222
	223	/* Close device */
	224	static int hci_uart_close(struct hci_dev *hdev)
	225	{
	226	BT_DBG("hdev %p", hdev);
	227
	228	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
	229	return 0;
	230
	231	hci_uart_flush(hdev);
3611f4d2	232	hdev->flush = NULL;
1da177e4 LT	233	return 0;
	234	}
	235
	236	/* Send frames from HCI layer */
7bd8f09f	237	static int hci_uart_send_frame(struct hci_dev hdev, struct sk_buff skb)
1da177e4	238	{
52bc423a	239	struct hci_uart *hu = hci_get_drvdata(hdev);
1da177e4 LT	240
	241	if (!test_bit(HCI_RUNNING, &hdev->flags))
	242	return -EBUSY;
	243
0d48d939	244	BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
1da177e4 LT	245
	246	hu->proto->enqueue(hu, skb);
	247
	248	hci_uart_tx_wakeup(hu);
0372a662	249
1da177e4 LT	250	return 0;
	251	}
	252
1da177e4 LT	253	/* ------ LDISC part ------ */
1da177e4 LT	254	/* hci_uart_tty_open
1687dfc3	255	*
1da177e4 LT	256	* Called when line discipline changed to HCI_UART.
	257	*
	258	* Arguments:
	259	* tty pointer to tty info structure
1687dfc3	260	* Return Value:
1da177e4 LT	261	* 0 if success, otherwise error code
	262	*/
	263	static int hci_uart_tty_open(struct tty_struct *tty)
	264	{
f327b340	265	struct hci_uart *hu;
1da177e4 LT	266
	267	BT_DBG("tty %p", tty);
	268
c19483cc AC	269	/* Error if the tty has no write op instead of leaving an exploitable
	270	hole */
	271	if (tty->ops->write == NULL)
	272	return -EOPNOTSUPP;
	273
089b1dbb	274	if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
7785162c	275	BT_ERR("Can't allocate control structure");
1da177e4 LT	276	return -ENFILE;
1da177e4 LT	277	}
0372a662	278
1da177e4 LT	279	tty->disc_data = hu;
1da177e4 LT	280	hu->tty = tty;
33f0f88f	281	tty->receive_room = 65536;
1da177e4	282
9f2aee84 JH	283	INIT_WORK(&hu->init_ready, hci_uart_init_work);
9f2aee84 JH	284
1da177e4 LT	285	spin_lock_init(&hu->rx_lock);
	286
	287	/* Flush any pending characters in the driver and line discipline. */
0372a662	288
1da177e4 LT	289	/* FIXME: why is this needed. Note don't use ldisc_ref here as the
1da177e4 LT	290	open path is before the ldisc is referencable */
0372a662	291
c65c9bc3 AC	292	if (tty->ldisc->ops->flush_buffer)
c65c9bc3 AC	293	tty->ldisc->ops->flush_buffer(tty);
f34d7a5b	294	tty_driver_flush_buffer(tty);
1da177e4 LT	295
	296	return 0;
	297	}
	298
	299	/* hci_uart_tty_close()
	300	*
	301	* Called when the line discipline is changed to something
	302	* else, the tty is closed, or the tty detects a hangup.
	303	*/
	304	static void hci_uart_tty_close(struct tty_struct *tty)
	305	{
	306	struct hci_uart hu = (void )tty->disc_data;
dac670b9	307	struct hci_dev *hdev;
1da177e4 LT	308
	309	BT_DBG("tty %p", tty);
	310
	311	/* Detach from the tty */
	312	tty->disc_data = NULL;
	313
dac670b9 JH	314	if (!hu)
dac670b9 JH	315	return;
22ad4203	316
dac670b9 JH	317	hdev = hu->hdev;
	318	if (hdev)
	319	hci_uart_close(hdev);
1da177e4	320
dac670b9 JH	321	if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
dac670b9 JH	322	if (hdev) {
9f2aee84 JH	323	if (test_bit(HCI_UART_REGISTERED, &hu->flags))
9f2aee84 JH	324	hci_unregister_dev(hdev);
dac670b9	325	hci_free_dev(hdev);
1da177e4	326	}
dac670b9	327	hu->proto->close(hu);
1da177e4	328	}
dac670b9 JH	329
dac670b9 JH	330	kfree(hu);
1da177e4 LT	331	}
	332
	333	/* hci_uart_tty_wakeup()
	334	*
	335	* Callback for transmit wakeup. Called when low level
	336	* device driver can accept more send data.
	337	*
	338	* Arguments: tty pointer to associated tty instance data
	339	* Return Value: None
	340	*/
	341	static void hci_uart_tty_wakeup(struct tty_struct *tty)
	342	{
	343	struct hci_uart hu = (void )tty->disc_data;
	344
	345	BT_DBG("");
	346
	347	if (!hu)
	348	return;
	349
	350	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	351
	352	if (tty != hu->tty)
	353	return;
	354
	355	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	356	hci_uart_tx_wakeup(hu);
	357	}
	358
1da177e4	359	/* hci_uart_tty_receive()
1687dfc3	360	*
1da177e4 LT	361	* Called by tty low level driver when receive data is
1da177e4 LT	362	* available.
1687dfc3	363	*
1da177e4 LT	364	* Arguments: tty pointer to tty isntance data
	365	* data pointer to received data
	366	* flags pointer to flags for data
	367	* count count of received data in bytes
1687dfc3	368	*
55db4c64	369	* Return Value: None
1da177e4	370	*/
55db4c64	371	static void hci_uart_tty_receive(struct tty_struct tty, const u8 data, char *flags, int count)
1da177e4 LT	372	{
1da177e4 LT	373	struct hci_uart hu = (void )tty->disc_data;
0372a662	374
1da177e4	375	if (!hu \|\| tty != hu->tty)
55db4c64	376	return;
1da177e4 LT	377
1da177e4 LT	378	if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
55db4c64	379	return;
0372a662	380
1da177e4	381	spin_lock(&hu->rx_lock);
55db4c64	382	hu->proto->recv(hu, (void *) data, count);
788f0923 CP	383
	384	if (hu->hdev)
	385	hu->hdev->stat.byte_rx += count;
	386
1da177e4 LT	387	spin_unlock(&hu->rx_lock);
1da177e4 LT	388
39c2e60f	389	tty_unthrottle(tty);
1da177e4 LT	390	}
	391
	392	static int hci_uart_register_dev(struct hci_uart *hu)
	393	{
	394	struct hci_dev *hdev;
	395
	396	BT_DBG("");
	397
	398	/* Initialize and register HCI device */
	399	hdev = hci_alloc_dev();
	400	if (!hdev) {
	401	BT_ERR("Can't allocate HCI device");
	402	return -ENOMEM;
	403	}
	404
	405	hu->hdev = hdev;
	406
c13854ce	407	hdev->bus = HCI_UART;
155961e8	408	hci_set_drvdata(hdev, hu);
1da177e4 LT	409
	410	hdev->open = hci_uart_open;
	411	hdev->close = hci_uart_close;
	412	hdev->flush = hci_uart_flush;
	413	hdev->send = hci_uart_send_frame;
6935e0f5	414	SET_HCIDEV_DEV(hdev, hu->tty->dev);
1da177e4	415
63c7d09c JH	416	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
	417	set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
	418
a55e1f38	419	if (!test_bit(HCI_UART_RESET_ON_INIT, &hu->hdev_flags))
a6c511c6	420	set_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
a55e1f38	421
8a7a3fd6 MH	422	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
	423	hdev->dev_type = HCI_AMP;
	424	else
	425	hdev->dev_type = HCI_BREDR;
	426
9f2aee84 JH	427	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
	428	return 0;
	429
1da177e4 LT	430	if (hci_register_dev(hdev) < 0) {
	431	BT_ERR("Can't register HCI device");
	432	hci_free_dev(hdev);
	433	return -ENODEV;
	434	}
	435
9f2aee84 JH	436	set_bit(HCI_UART_REGISTERED, &hu->flags);
9f2aee84 JH	437
1da177e4 LT	438	return 0;
	439	}
	440
	441	static int hci_uart_set_proto(struct hci_uart *hu, int id)
	442	{
	443	struct hci_uart_proto *p;
0372a662 MH	444	int err;
0372a662 MH	445
1da177e4 LT	446	p = hci_uart_get_proto(id);
	447	if (!p)
	448	return -EPROTONOSUPPORT;
	449
	450	err = p->open(hu);
	451	if (err)
	452	return err;
	453
	454	hu->proto = p;
	455
	456	err = hci_uart_register_dev(hu);
	457	if (err) {
	458	p->close(hu);
	459	return err;
	460	}
0372a662	461
1da177e4 LT	462	return 0;
	463	}
	464
	465	/* hci_uart_tty_ioctl()
	466	*
	467	* Process IOCTL system call for the tty device.
	468	*
	469	* Arguments:
	470	*
	471	* tty pointer to tty instance data
	472	* file pointer to open file object for device
	473	* cmd IOCTL command code
	474	* arg argument for IOCTL call (cmd dependent)
	475	*
	476	* Return Value: Command dependent
	477	*/
	478	static int hci_uart_tty_ioctl(struct tty_struct tty, struct file file,
0372a662	479	unsigned int cmd, unsigned long arg)
1da177e4 LT	480	{
	481	struct hci_uart hu = (void )tty->disc_data;
	482	int err = 0;
	483
	484	BT_DBG("");
	485
	486	/* Verify the status of the device */
	487	if (!hu)
	488	return -EBADF;
	489
	490	switch (cmd) {
	491	case HCIUARTSETPROTO:
	492	if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
	493	err = hci_uart_set_proto(hu, arg);
	494	if (err) {
	495	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
	496	return err;
	497	}
0372a662	498	} else
1da177e4	499	return -EBUSY;
c33be3c3	500	break;
1da177e4 LT	501
	502	case HCIUARTGETPROTO:
	503	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	504	return hu->proto->id;
	505	return -EUNATCH;
0372a662	506
d2158744 MH	507	case HCIUARTGETDEVICE:
	508	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	509	return hu->hdev->id;
	510	return -EUNATCH;
	511
63c7d09c JH	512	case HCIUARTSETFLAGS:
	513	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	514	return -EBUSY;
	515	hu->hdev_flags = arg;
	516	break;
	517
	518	case HCIUARTGETFLAGS:
	519	return hu->hdev_flags;
	520
1da177e4	521	default:
47afa7a5	522	err = n_tty_ioctl_helper(tty, file, cmd, arg);
1da177e4	523	break;
a20890d0	524	}
1da177e4 LT	525
	526	return err;
	527	}
	528
	529	/*
	530	* We don't provide read/write/poll interface for user space.
	531	*/
0372a662 MH	532	static ssize_t hci_uart_tty_read(struct tty_struct tty, struct file file,
0372a662 MH	533	unsigned char __user *buf, size_t nr)
1da177e4 LT	534	{
	535	return 0;
	536	}
0372a662 MH	537
	538	static ssize_t hci_uart_tty_write(struct tty_struct tty, struct file file,
	539	const unsigned char *data, size_t count)
1da177e4 LT	540	{
	541	return 0;
	542	}
0372a662 MH	543
	544	static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
	545	struct file filp, poll_table wait)
1da177e4 LT	546	{
	547	return 0;
	548	}
	549
1da177e4 LT	550	static int __init hci_uart_init(void)
1da177e4 LT	551	{
a352def2	552	static struct tty_ldisc_ops hci_uart_ldisc;
1da177e4 LT	553	int err;
	554
	555	BT_INFO("HCI UART driver ver %s", VERSION);
	556
	557	/* Register the tty discipline */
	558
	559	memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
0372a662 MH	560	hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
	561	hci_uart_ldisc.name = "n_hci";
	562	hci_uart_ldisc.open = hci_uart_tty_open;
	563	hci_uart_ldisc.close = hci_uart_tty_close;
	564	hci_uart_ldisc.read = hci_uart_tty_read;
	565	hci_uart_ldisc.write = hci_uart_tty_write;
	566	hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
	567	hci_uart_ldisc.poll = hci_uart_tty_poll;
0372a662 MH	568	hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
	569	hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
	570	hci_uart_ldisc.owner = THIS_MODULE;
1da177e4 LT	571
	572	if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
	573	BT_ERR("HCI line discipline registration failed. (%d)", err);
	574	return err;
	575	}
	576
	577	#ifdef CONFIG_BT_HCIUART_H4
	578	h4_init();
	579	#endif
	580	#ifdef CONFIG_BT_HCIUART_BCSP
	581	bcsp_init();
	582	#endif
166d2f6a OBC	583	#ifdef CONFIG_BT_HCIUART_LL
	584	ll_init();
	585	#endif
b3190df6 SS	586	#ifdef CONFIG_BT_HCIUART_ATH3K
	587	ath_init();
	588	#endif
7dec65c8 JH	589	#ifdef CONFIG_BT_HCIUART_3WIRE
	590	h5_init();
	591	#endif
166d2f6a	592
1da177e4 LT	593	return 0;
	594	}
	595
	596	static void __exit hci_uart_exit(void)
	597	{
	598	int err;
	599
	600	#ifdef CONFIG_BT_HCIUART_H4
	601	h4_deinit();
	602	#endif
	603	#ifdef CONFIG_BT_HCIUART_BCSP
	604	bcsp_deinit();
	605	#endif
166d2f6a OBC	606	#ifdef CONFIG_BT_HCIUART_LL
	607	ll_deinit();
	608	#endif
b3190df6 SS	609	#ifdef CONFIG_BT_HCIUART_ATH3K
	610	ath_deinit();
	611	#endif
7dec65c8 JH	612	#ifdef CONFIG_BT_HCIUART_3WIRE
	613	h5_deinit();
	614	#endif
1da177e4 LT	615
1da177e4 LT	616	/* Release tty registration of line discipline */
64ccd715	617	if ((err = tty_unregister_ldisc(N_HCI)))
1da177e4 LT	618	BT_ERR("Can't unregister HCI line discipline (%d)", err);
	619	}
	620
	621	module_init(hci_uart_init);
	622	module_exit(hci_uart_exit);
	623
63fbd24e	624	MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
1da177e4 LT	625	MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
	626	MODULE_VERSION(VERSION);
	627	MODULE_LICENSE("GPL");
	628	MODULE_ALIAS_LDISC(N_HCI);